Most of the information below is specific to the United States. For H1N1 flu vaccine information for the country you live in, please contact or visit the website of your country's health department.

What Is the Pandemic (H1N1) Influenza Vaccine?

A
vaccine
is a substance used to protect people from infections caused by bacteria and viruses. The
H1N1 flu vaccine
is designed to protect you against the
pandemic H1N1 flu virus
. There are two ways you might receive the H1N1 flu vaccine:

Shot given in the muscle—uses inactivated vaccine containing dead virus

Nasal spray—uses live, attenuated vaccine containing weakened virus

The virus in a vaccine will not make you sick.

Like other flu vaccines, you should not get the H1N1 flu vaccine if you are allergic to eggs.

The live, attenuated vaccine (nasal spray) should not be given to:

Those younger than two years or older than 50 years

Anyone with a severe chronic medical condition or weakened immune system

Pregnant women

Children under 18 years old taking chronic aspirin therapy

When Will the Vaccine Become Available?

Availability differs from country to country. Check with your country's health department to find out if the H1N1 flu vaccine is available. The vaccine is now available in the United States and in the United Kingdom.

Who Will Distribute the Vaccine?

In the United States, the CDC will distribute the H1N1 flu vaccine to every state. Each state will then determine how the vaccine is distributed, depending on quantity and need. It will be available to health departments, clinics, hospitals, and businesses in the public and private sectors.

Who Will Get the Vaccine?

In the United States, the CDC has indicated high-risk groups who will be targeted first:

Pregnant women

People who live with or care for children younger than six months old

Healthcare and emergency medical services personnel

People aged six months to 24 years

People aged 25-64 years who are at higher risk for pandemic H1N1 flu because of chronic health disorders (eg,
asthma
) or weak immune systems

The Public Health Agency of Canada has similar target groups to the CDC but also include:

People living in remote areas

People handling pigs or poultry

People in these target groups who have had flu-like illness not confirmed to be pandemic H1N1 flu should still be vaccinated.

After the target groups, people aged 25-64 years should get the vaccine. Older adults (over 65 years) will be the last group to receive the vaccine. (Older adults have been less likely to become infected with this flu than younger people.)

When Should I Get the Vaccine?

Flu season can begin as early as October and as late as April or May. The best time to get vaccinated is as soon as the vaccine becomes available. Doing so will protect you before the flu comes to your community. The flu season can extend into the spring, so it is important to still get vaccinated if you did not do so early in the season.

What Happens in the Event of a Vaccine Shortage?

Local public health officials will distribute the H1N1 flu vaccine based on risk and need in the communities.

Target populations would consist of:

Pregnant women

Anyone who lives with or cares for a child under the age of six months

Healthcare workers and emergency medical personnel

People aged six months to four years

Children aged 5-18 years with chronic medical conditions

How Will the Vaccine Be Given?

The H1N1 flu vaccine will come in different forms such as shot and nasal spray. There will be multi-dose vials for wide distribution to the general public and single-dose vials without preservatives for pregnant women and children.

Who Will Pay for the Vaccine?

The United States federal government will buy the H1N1 flu vaccine from the manufacturers.

Will I Have to Pay to Get the Vaccine?

The H1N1 flu vaccine will be free at public health vaccination clinics. Private healthcare providers and institutions may charge a fee. This fee is usually covered by insurance companies.

How Many Vaccinations Will I Need?

The nasal spray will be given in two doses (given one month apart) for children aged 2-9 years and in one dose for persons aged 10-49 years. The shot will be given in two doses (given one month apart) to children aged six months to nine years and in one dose for people aged 10 years and older. Make sure you talk to your healthcare provider about which vaccine is right for you.

If I Get the Vaccine Does That Mean I Will Not Get the Pandemic H1N1 Flu?

Even if you have been vaccinated, you can still get the pandemic H1N1 flu. If you have symptoms, tell your doctor.

Can I Get the H1N1 Flu and Seasonal Flu Vaccines at the Same Time?

Yes, you can get the H1N1 flu vaccine at the same time as other vaccines, including the
seasonal flu vaccine
.

You can get the following vaccines at the same time:

Seasonal flu shot and H1N1 flu shot

Seasonal flu shot and H1N1 flu nasal spray vaccine

Seasonal flu nasal spray vaccine and H1N1 flu shot

You should
NOT
get the seasonal flu nasal spray vaccine and the H1N1 flu nasal spray vaccine at the same time. If you want to have both nasal spray vaccines, you will need to get them at least two weeks apart from each other, one month apart is best.

If both nasal spray vaccines are given less than two weeks apart, you may need another dose of the last vaccine given. For example, if you were given the H1N1 flu nasal spray and then had the seasonal flu nasal spray 10 days later, you will need another dose of the seasonal flu nasal spray at least two weeks (one month is best) after the first seasonal flu dose.

If I Was Given the Vaccine in 1976 for Swine Flu, Will I Need to Get the H1N1 Flu Vaccine?

The 1976 swine flu virus and the pandemic H1N1 flu virus are different. If you were vaccinated in 1976, it is unlikely you will be protected from the pandemic H1N1 flu. People vaccinated in 1976 should still get the H1N1 flu vaccine.

Is the Vaccine Safe?

Side effects are rare with the influenza vaccines. In 1976 there was concern that the influenza vaccine was linked to
Guillain-Barre syndrome
(a rare disease of the nervous system triggered by infections). Since that time the vaccine has not been linked to this disorder. The risk of Guillain-Barre Syndrome from an influenza vaccine is estimated to be 1 case per million vaccinations.

Like the seasonal flu vaccine, the H1N1 flu vaccine is expected not to cause problems other than soreness at the injection site. People with specific allergies (eggs, latex, or certain drugs) should check with their doctor before receiving any flu vaccine.

The live, attenuated vaccine (nasal spray) should not be given to:

Those younger than two years or older than 50 years

Anyone with a severe chronic medical condition or weakened immune system

Pregnant women

Children under 18 years old taking chronic aspirin therapy

Can I Give My Child Acetaminophen to Prevent a Fever and Pain After He Is Vaccinated?

A
study by researchers from the Czech Republic
showed that giving acetaminophen (eg, Tylenol) to a child at the time of vaccination decreased the chance of developing a fever, but it may also lower the effectiveness of certain vaccines. The researchers did not study the effect of acetaminophen on flu vaccines. Talk to your child's doctor to see whether acetaminophen should be used when your child is getting a vaccine.

This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.

Centers for Disease Control and Prevention. Asthma information for patients and parents of patients. Centers for Disease Control and Prevention website. Available at:
http://www.cdc.gov/H1N1flu/asthma.htm
. Updated September 15, 2009. Accessed September 15, 2009.

Centers for Disease Control and Prevention. It’s flu season: learn how to protect yourself and your loved ones. Centers for Disease Control and Prevention website. Available at:
hhttp://www.cdc.gov/Features/flu/
. Updated September 21, 2009. Accessed September 23, 2009.

United States Food and Drug Administration. Influenza A (H1N1) 2009 monovalent vaccines questions and answers. United States Food and Drug Administration website. Available at
http://www.fda.gov/BiologicsBloodVaccines/Vaccines/QuestionsaboutVaccines/ucm182335.htm
. Updated September 15, 2009. Accessed September 17, 2009.